Earlier this month, I installed a new serpentine belt (NAPA #060535) to ensure I had that last Nth of performance that a slipping belt causes you to loose, and changed my injectors from the stock 340cc units to up-rated 380cc ones. Why?

In preparation for being tuned by the master, Jan Brueggemann from Revolution Mini Works. He came for a week-long tuning session at Helix Minisports in Philadelphia. I was scheduled for Tuesday the 22nd.

We rushed down (it’s a 4.5hr trip to Philly), ate some food, waited, and then my car was strapped on the dyno. The wonky alignment caused the car to act dangerous on the dyno, but dialing back the camber (and going from toe out to toe in) solved that problem. The car pulled strong numbers right off the bat, but the dyno kept “creeping down” and the numbers got worse, even with the tune. After countless pulls and probably close to three hours on the dyno, going back and forth from stock to tuned maps, Jan was finally happy with the results. He made sure they were repeatable and safe.

With the new-found power comes a revolutionary level of refinement and silky smoothness. MINI left a lot on the table with their stock tuning, and with the modifications it was a bear to drive smoothly. This tune brought refinement, AND made DSC (traction control) less intrusive.

It turns out the car was running lean when cold. I was surprised, considering how rich it ran the rest of the time. The car is also mercifully getting better gas mileage, which plummeted for the week that I had the injectors installed but no tune. I averaged 24.6 mpg going down at an average of 80mph. It was 29 mpg coming back at the same speed. I should be doing consistent 30s come summertime again.

Where are the dyno plots, you ask? Why, right here! Notice the 15-20 lb-tq gain down low, and the 15 whp gain up high. The “area under the curve” is expressed as the averages on the lower right-hand corner. Run 2 is before and run 1 is after. The gains are great. MINIs never used to hit 200whp without serious work like a head – and this is all on an inertia-type Mustang dyno, not some seedily optimistic dynojet. I am quite satisfied power-wise for the time being.

(Click to make bigger.)